This Automotive Head Up Display is abbreviated to HD and short for Head Up Display,
with the meaning of \'Look-up display device\',
or \'Look-at-the-fronthorizontally display device\'.
It can project the important information(e.g.vehicle speed)
onto the front windshield at the eye level of the driver
and thus help to make their driving safe and sound when driving at a high speed,
especially at night without lowering their heads.
